Field of Invention
The present invention relates to a system and a method for recognizing stamped characters and a system for detecting stamped depths of characters using the same, and more particularly, to a technology of recognizing a stamped vehicle identification number and a technology of detecting stamped depths of stamped characters using the same.
In the present specification, the stamped character means a letter (Hangeul, English, and the like) and a number carved in a solid object, such as metal, in intaglio or relief.
Description of Related Art
Stamping a vehicle identification number (VIN) in a partition wall between an engine room and a driver's seat within a bonnet of a vehicle is required by law.
The vehicle identification number includes an alphabet and a number to indicate a producing country, a manufacturer, a vehicle division, a vehicle model, a detailed vehicle model, a vehicle body shape, a safety device type, displacement, a driver's seat position, a manufactured year, a manufacturing factory, and a producing serial number.
In general, a stamping system is implemented in a robot type that is automatically controlled by a process program and manually controlled by a user and includes a stamped tool (pin) in which a stamped pin is mounted at an end of an arm of the robot.
When a body in white (BIW) that is a workpiece enters a work location, the stamping system determines a position of a vehicle body and a position of the stamped tool, fixes the body in white, and then operates the stamped pin according to a pneumatic control to stamp the vehicle identification number.
Further, the stamping system includes an apparatus for recognizing stamped characters to perform a process of confirming whether the vehicle identification number is accurately stamped.
The apparatus for recognizing stamped characters according to the related art includes two light emitting diode (LED) lighting devices having the same wavelength and one mono camera and uses the two LED lighting devices to irradiate LED lighting to a surface carved with characters at a right angle and then uses the mono camera to photograph the stamped characters. That is, images for the stamped characters are acquired by using a direct irradiation method.
Therefore, when the stamped depths of characters are different due to the wear of the stamped pins, a distorted image occurs at the stamped portions due to scattered reflection and concentration of light caused by a difference in angles of the stamped portions, which leads to the recognition error of the vehicle identification number.
Therefore, even though the stamped pins are worn, a need exists for a method for accurately recognizing stamped characters.
The information disclosed in this Background section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art.